Scan Tool Data Definitions

WARNING: This page is about a different car, the 2002 Oldsmobile Aurora and 2001 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.

Coolant Level: The scan tool displays OK or Low. This parameter indicates the level of the coolant in the surge tank.

ECT Sensor: The scan tool displays -40°C to +150°C (-40°F to +302°F). The Engine Coolant Temperature (ECT) sensor is mounted in the coolant stream. The Powertrain Control Module (PCM) applies 5 volts to the ECT sensor circuit. The sensor is a thermistor which changes internal resistance as the temperature changes. When the sensor is cold (internal resistance high), The PCM monitors a high signal voltage and interprets it as a cold engine. As the sensor warms (internal resistance decreases), the voltage signal decreases and the PCM interprets the lower voltage as a warm engine.

FC Relay 1 Circuit Status: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

FC Relay 1 Command: The scan tool displays On or Off. The PCM is commanding Fan Control Relay 1 On when the scan tool indicates On. When the PCM commands the Fan Control Relay 1 On, both fans are enabled at low speed.

FC Relay 2 and 3 Circuit: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

FC Relay 2 and 3 Command: The scan tool displays On or Off. The PCM is commanding all three fan control relays On when the scan tool indicates On. When all fan control relays are activated, both cooling fans are enabled at high speed.